Control for automatic transmissions



Plll 11, 1950 R. BRUNKEN ET Al.

v CONTROL FOR AUTOMATIC TRANSMISSIONS Filed Jan. 8. 1947 INVENTORS MD mmNWC U05 EH# ,w BRI e Y. T n EE E T KME MAM RWoa. ,AH

Patented pr. 11i, 195() UNITED STATES PATENT OFFICE CONTROL FORAUTOMATIC TRANSMISSIONS tion of Ohio Application January S, 1947 SerialNo. 720,838

(Cl. 'Z4-731') 13 Claims.

This invention in its preferred application re lates to transmissionsfor motor vehicles and is specifically directed to improved mechanismfor the control of transmissions which include both a fluidtransmission, such as a torque converter or hydraulic coupling, and amechanical change speed gear such as the, conventional selective slidinggearbox or a planetary transmission.

Automatic transmissions incorporating both hydraulic and' mechanicalelements are disclosed in U; S. Patent No.2,373fl53 of April l0, 1945'to Henke Brunk'en for Automatic gear shifting mechanism for transmissionPatent No. 2,499,128 dated February v28, 1950 of Renke Brunken for aTorque converter control; Patent No. 2,498,600 dated February 21, 1950of Renke Brunken for Hydraulic transmission and controlmechanismtherefor; and Patent No. 2,484,011, dated October 11, 1949 of RenkeBrunken and Raymond Haag for Electric control mechanism forv automatictransmission. All these transmissions include automatic mechanism forshifting gear in a mechanical transmission controlled by the speedrelationship of the driving and driven elements of a torque converterthrough which L power is supplied from the engine tothe gearbox.

These prior disclosures al1 involve the use of a speed responsive devicedriven byl one element of a differential gear, the other two elementsofv which are driven from 'parts Vof the engine or transmission whichrotate at speeds proportional to those of the pump yand turbine of thetorque converter respectively. The gearing is such that the responsivedevice is driven at a speed which is a difference-functionofthelsp'e'eds'of the pumpl and'turbine.

Previously, the contemplated arrangement of.: the control device was toinstall the speed' responsive device `and differential gear as a unitremote from the engine and transmission and to drive the unit throughflexible shafts of the gen'- eral type used for speedometer'drivesvandthe like.-v

The presentv invention` is directed to an improved construction byvirtue-of which the differ-l ential gear and the drivingv mechanismtherefor may be installed Within the transmission housing and thespeedresponsive device, which usually takes the form of a centrifugalswitch, and which will be called4 a. governor hereafter for brevity, isremovably mounted on the outside of the transmission housing in such away asto be driven directly by the output ofthe differential gearing.

In this way, flexible shafting is. eliminated, greater reliability issecured, lubrication problems are eliminated', and a more compactinstallation is obtained. The invention involves a novel design of thediierential gear unit, the drive gearing and the transmission housing tofacilitate assembly and disassembly while retaining ruggedness andavoiding interference with the transmission mechanism as' such.

The invention is illustrated herein as incorporated in a transmissionwhich is, in all relevant particulars, substantially identical with thatdescribed in the abovementioned Patent No. 2,498,600; The descriptionherein willtherefore, be` confined to. the differential gearing and thedriving connections therefor, `without repeating the detailsv ofthetransmission perse or its control'instrumentalities.

Referring to the drawings:

Fig. 1 is a transverse vertical section of a transmissionl incorporatingthe invention;

Fig. 2 is an enlarged view of a portion of Fig. 1 to show certainfeatures more clearly; and

Fig. 3 is a schematick perspective drawing of th'e'gearing.

The general nature of the invention may best be understood' by referringto the schematic drawing of Fig. 3, in which il is a spur gear mountedonthe rear parti-of the torque converter casing, which is directlycoupled with the engine of the vehicl'eand Within which are fixed thevanes of the driving memberor pump of the torque converter. A spiralgear l2 is fixed on the forward end of the countershaft of the gear box.The countershaft is constantly driven by the main shaft of thetransmission which is permanently coupled tothe driven member or turbineof the torque converter. Gears il and l2 are therefore driven at speedsproportional to those of the driving and driven members of the hydraulictransmission, respectively. A spur gear I3 meshing with the gear H ismounted on a shaft Hl on Which is also mounted a spiral gear l5. Theshaft ls is parallel to the transmission main and countershafts. Thespiral gear i5 drives a spiral gear |`6 which is coupled tothe cage orspider Il of the differential gear, which has bevel planet'wheels I'8rotatably mounted therein. The spiral gear l2 drives `a spiral gear 2ifixed on a horizontal shaft 22 directed transverselyof the transmission.A bevelgear 2`3 on the-shaft 22 drives a bevel gear 24' on a verticalshaft 25 which extends through the gear Iii and thelovver part of thespider `I1 and has a bevel'sun gear 26 mounted on its upperendmeshing'withthe planet gears i8. The -other sun gear 2T ofthediiierenti'al gear is coupled toa centrifugal circuit closing deviceor governor 39 which is connected by leads 3| to the electricalY 3system which controls shifting of the gears in the gear box.

With the pump and turbine rotating in the same direction, which is thenormal mode of operation, the spider I1 and sun gear 26 are rotated inthe same direction. Rotation of the spider tends to rotate the sun gear21 in the same direction, whereas rotation of the sun gear 26 tends torotate the sun gear 21 in the opposite direction. The rotation of thesun gear 21 and governor 30 is thus a difference-function of therotations of the pump and turbine. The gear ratios are so calculatedthat these two inputs cancel out and the sun gear 21 is stationary at adesired control point which is approximately the condition of equalrotation of the pump and turbine. The point of zero rotation of the sungear 21 is determined with respect to the characteristics of the engine,torque converter, gear box, and vehicle, and the performance desired ofthe vehicle. The principles of operation of the system are described inthe above-mentioned patent and applications.

Referring to Fig. 1, the mechanism so far described is mounted in and ona housing 40 which is shown partially cut away and which bolts to acompanion housing (not shown) fixed to the engine to form an enclosurefor the torque converter. Fig. 1 is a vertical section through the rearpart of the housing looking toward the torque converter. The gear case(not shown) is bolted to the rear part of the housing 40. The gear case,the housing 48, and the companion housing bolted to the engine form afunctionally unitary housing for the entire transmission. Gear Il, whichis xed to the rear face of the tor que converter casing in anyconvenient manner, drives the gear I3 which is rotatably mounted on abushing 42 supported by a stub shaft 43 extending from a vertical faceof the housing 40. The spiral gear I is pressed on to a rearwardlyextending hub 44 of the gear |3, the gears I3 and |5 thus rotating as aunit on the bushing 42. The spiral gear |2 is xed in any convenientmanner on the forward end of the gearset countershaft 46 which projectsforward into the torque converter housing. Gear I2 drives the spiralgear 2| fixed on the horizontal shaft 22 which is rotatably mounted inbushings 41 and 48 in the casting 40. The bevel gear 23 is secured tothe shaft 22 by a nut 49 and is formed with a hub portion which isjournalled in the bushing 48. An access plate 5| secured by cap screws52 covers an opening 53 through which the gears 23 and 2| and shaft 22may be withdrawn. It will be understood, of course, that all gears inthe mechanism may be keyed or splined to their shafts according to usualpractice.

The spiral gear I6 which meshes with the gear |5 is formed integral withan elongate hub 54, the lower end of which is formed with a flange 55and is journalled in a bushing 56 which provides radial and thrustbearing surfaces for the hub. The bushing 56 is fitted in a bore in abracket extending inwardly from the vertical side wall portion of thecasting 40. The arrangement for supporting the upper end of the hub 54is shown more clearly in Fig. 2. A bushing 51 formed with a flange 58 isfitted in a recessed bore 59 in a transverse web 6| of the housing 40.The bushing is held against rotation by a cap screw 62 threaded into thehousing and entering a slot 63 in the ouer wall of the bushing 51. Theupper end of the hub 54 is journalled in a bearing sleeve 64 in thebushing 51 and a thrust bearing Washer 66 is fitted between the lowerface of the bushing 51 and the flange 61 of the hub. The bevel gear 24,Fig. 1, is secured to the lower end of the shaft 25, (Figs. 1 and 2) bya nut 68. The shaft 25 is journalled in bushings 69, (Fig. 1), and 1|,(Fig. 2), pressed into the central bore 12 of the hub 54.

A cover plate and governor mounting bracket 13 is mounted on ahorizontal upper surface 14 of the housing 40 by studs and nuts 16 andis formed with a portion 11 which enters an aperture 18 in the housingto secure exact alignment of the bracket 13. The under surface of theplate 13 is formed with an annular boss 19 on which is rotatably mountedthe differential cage I1, a bearing sleeve 8| being provided. The lowerend of the differential cage is formed with an extension 82 disposedwithin the bore in the bushing 51. The cage is held against longitudinalmovement by the bushing 51 and the cover plate 13. The differential cage|1 is of usual form, and mounts a transverse shaft 83 held in place by apin 84. The planet gears I8 are mounted on the shaft 83 and separated bya spacer block 86. The sun gear 26 is formed integral with the upper endof the shaft 25, the cage |1 is j ournalled on the shaft by a thrust andradial bearing sleeve 81. The upper end of the hub 54 and the lower end82 of the differential cage are in close proximity to each other withinthe bushing 51 and are formed with dog teeth 99 so that the cage l1 ispositively driven by the gear I6. The planet gear 21 is formed integralwith a shaft 88 journalled in a bushing 89 fitted in a central bore ofthe bracket 13. The two sun gears mesh with the planet gears in theusual manner. The governor 30, Fig. 1, is provided with a base portion9| which is threaded into the tapped upwardly extending boss 92 of thecover plate 13 and is thus readily removable. The drive shaft 94 of thegovernor is formed with a square central hole and the shaft 88 likewisehas a square central opening, square key 96 received within the shaftscoupling the shafts 88 and 94 together. An oil drain hole 91 is drilledthrough the plate 13. The governor 36 is a centrifugal switch, thedetails of which form no part of the -present invention. Since suchswitches are commercially available, the details of the governor 30 willnot be described herein.

The assembly shown herein is particularly adapted to ease of repair andreplacement of parts. The governor 30 may be unscrewed from the coverplate, the key 96 permitting ready removal of the governor. By takingout the nuts 16, the cover plate 13 may be lifted off. Planet gear 21may then be removed through the upper opening in the cage I1. By takingoff the cover plate 5|, the bevel gear 24 and the shaft 22 with itsgears may be taken out. Removal of the screw 62 provides clearance forthe rest of the mechanism to be pushed through the holes 59 and 18. Theopening 18 is large enough to pass the bushing 51, and the hole 59 willpass the gear I6. The gear 24 may be made smaller than the lower journalof the hub 54 so that the assembly may be removed without taking bevelgear 24 off.

Although the foregoing description is necessarily of a detailedcharacter, in order that the invention may be completely set forth, itis to be understood that the specific terminology is not intended to berestrictive or confining, and that various rearrangements of parts andmodi--v as herein claimed.

We claim:

1. In an automaticftransrnission comprising a hydraulic drive member, anannular casing for the drive member rotatable therewith, a `hydraulicdriven memberwithin the casing and mounted on a shaft extendingtherefrom, a gearset including a main shaft, the main shaft constitutingan extension of the driven membershaft, and a fixed housingr for thehydraulic members and gearset: a speed-responsive` device, means formounting the speed-responsive device on the housing, a differential gearWithin the housing, means for coupling the speed-responsive device toone side ofthe differentialv gear for rotation thereby, concentricshafts for driving the spider and other side of thev differential,A agear on ythe casing, a gear driven from 'the main shaft, andv meanswithin the housing for driving the concentric shafts from the twolast-named gears respectively.

2. In an automatic transmission comprising a hydraulic drive member, anannular casing for the drive member rotatable therewith, a hydraulicdriven member within the casing and mounted on a shaftextendingtherefrom, a gearset including a main shaft and a countershaftdriven thereby, the main shaft constituting an extension of the drivenmember shaft, and' a fixed housing for the hydraulic membersvaruigearset: a speedresponsive device, meansffo'r mountingthespeedresponsivedevice externally 'of' theV housing, a differential gearwithin the housing, means for coupling the speed-responsive device toone side of the differential gear for'rotation thereby, concentricshafts for driving the spider and other side of the differential, 'agear on the casing, a gear on the counterShaft, and means within thehousing for driving the concentric shafts from the casing gear andcountershaft` gear respectively.

3. In combination, va fluid transmission including a pump and a turbine,a gearbox including a main shaft driven by the turbine, and meansresponsive to the speedA relation of the pump and turbine forcontrolling shifting of, gears in the gearbox, the lastenamed Vmeanscomprising'- a rst gear on the pump, arrst shaft directed longitudinallyof the gearbox and driven by the first gear, a hollow shaft driven bythe first shaft, a second shaftdirected transversely of the gearbox anddriven from the main shaft, a third shaft mounted within the hollowshaft and driven.

by the second shaft, a differentialv gear having three elements, twoofthe elements being drivenv by the hollow shaft and'third shaftrespectively, and a speed-sensitive device driven by the third element.

4. In combination, a fluid transmission including a pump and a turbine,a gearboxl including a main shaft and a countershaft, the main shaftbeing driven by the-turbine, and means responsive to the speed relationof the pump and turbine for.

controlling shiftingof gears-in thegearbox, the last-namedmeanscomprising a irstgear on the pump, a first shaft directed longitudinallyof the gearbox and driven .bythe first gear, a hollow shaft driven bythe yrst shaft, a `second gear on the countershaft, a second shaftdirected trans-` versely of the gearbox and ydriven by the second gear,a third shaft'mountedwithin the hollow4 shaft and `driven bythefsecondshaft, aldifferential gear having three elementatwo ofthe ele- 6 mentsbeing drivenby the hollow 'shaft and" third shaft respectively, yand aspeed-sensitive devicel driven by the third element.

5. In combination, a fluid transmission includ--y ing a pump and aturbine, a gearbox .including a main shaft anda countershaft,the-mainshaft: being driven by the turbine, and meansV respon-A sive tothe speed relation of lthe Ypump-andvr tur-v bine for controllingshifting cfgears in the ygear box, the last-named means comprising a'first gear on the pump, a rst shaft directed longitudinally of the gearbox and driven bythe first gear, a hollow shaft driven by the firstshaft,v a second gear on the countershaft, a second-shaft.

directed transverselyof the: gearbox and driven..

a main shaft and a countershaft, the main'shaft;

being driven by the turbine, and' means respon-l sive to the speedrelation offthepump' andturw bine for controlling shifting of-gears inthe gearbox, the last-named means comprising a rst,

gear on the pump, a rst shaft directed longitudinally of the gearbox anddriven by the' first gear, a hollow shaft driven bythe first shaft;

a second gear on the countersh'aft, a -secondshafti directedtransversely ofv the gearbox and driven by the second gear, athird-shaftmountedwithin the hollow shaft and driven by the secondshaft,l a dinerential gear having -three elements, two

of the elements being Idriven bythe hollow shaftv and third shaftrespectively, and a speed-sensitive device mounted on the gearboxexternally thereof. and driven by the third element.

7. In combination, a fluid ltransmission including a pump and a turbine,a gearbox including a main shaft driven by the turbine, and meansresponsive to the speed relation of the pump and turbine for controllingshifting of gears in thegearbox, the last-named means comprising aifirst gear on the pump, af first-shaft directed .longitudinally of thekgearbox and drivenby the first gear, a hollow shaft'driven by the firstshaft, a second shaft directed transversely of the gearbox and drivenfrom the shaft mounted within the hollow shaft and driven by the secondshaft, a differential gear having a cage driven by the hollow shaft'andone side gear driven by the third shaft,` and aspeedsensitive devicedrivenby the other side gear of the differential, the hollow shaft andthird shaft normally rotating in the same direction.

8. A differential governor adapted for mount-Vr ing on a transmissionhousing comprising a cover mounting'over an opening inthe housing, aspeed-responsive device mountable-` on the cover plate outsidethehousing, ya drive` plate adapted for shaft for the responsive devicejournalled ein the cover plate, a differential gearV assembly having oneelement coupled to the drive shaft and'being rotatably supported by thecover plate, a sleeve journalling the gear assembly and adaptedto be.

fitted in an aperture kin a first bracket in the housing, a hollow shafthaving a gear thereon; journalled at one end in the sleeve adjacentthe-'f gear assembly, the hollow shaft and one element: of thedifferential gear beingfclutch'ed"together-g mainv shaft, a third` thegear being of smaller diameter than the sleeve and aperture and thesleeve of smaller diameter than the opening in the housing, the otherend of the hollow shaft being adapted for rotation in an aperture in asecond bracket in the housing, a central shaft journalled in andextending through the hollow shaft and coupled to the third element ofthe differential gear, and a drive gear mounted on the central shaftexternal to the hollow shaft, the drive gear being small enough to passthrough the apertures and the opening.

9. A differential governor adapted for mounting on a transmissionhousing comprising a cover plate adapted for mounting over an opening inthe housing, a speed-responsive device mountable on the cover plateoutside the housing, a drive shaft for the responsive device journalledin the cover plate and having a first sun pinion thereon, a differentialcage circumjacent the pinion and rotatably supported at one end by thecover plate, a sleeve journalling the other end of the cage and adaptedto be fitted in an aperture in a first bracket in the housing, a hollowshaft having a gear thereon, journalled at one end in the sleeveadjacent the cage, said hollow shaft and the cage being clutchedtogether, the gear being of smaller diameter than the sleeve andaperture and the sleeve of smaller diameter than the opening in thehousing, the other end of the hollow shaft being adapted for rotation inan aperture in a second bracket in the housing, planet gears in the cagemeshing with the first sun pinion, a second sun pinion meshing with theplanet gears and mounted on a central shaft journalled in and extendingthrough the hollow shaft, and a drive gear mounted on the central shaftexternal to the hollow shaft, the drive gear being small enough to passthrough the apertures and the opening.

10. In combination with a transmission housing, a differential governoradapted for mounting on the housing comprising a cover plate adapted formounting over an opening in the housing, a speed-responsive devicemountable on the cover plate outside the housing, a drive shaft for theresponsive device journalled in the cover plate and having a first sunpinion thereon, a differential cage circumjacent the pinion androtatably supported at one end by the cover plate, a

first bracket in the housing, a sleeve journalling the other end of thecage and adapted to be fitted in an aperture in the rst bracket, ahollow shaft having a gear thereon, journalled in the sleeve adjacentthe cage, said hollow shaft and cage being clutched together, the gearbeing of smaller diameter than the sleeve and aperture and the sleeve ofsmaller diameter than the opening in the housing, a second bracket inthe housing, the other end of the hollow shaft being adapted forrotation in an aperture in the second bracket, planet gears in the cagemeshing with the first sun pinion, a second sun pinion meshing with theplanet gears and mounted on a central shaft journalled in and extendingthrough the hollow shaft, and a drive gear mounted on the central shaftexternal to the hollow shaft, the drive gear being small enough to passthrough the apertures and the opening.

11. A differential governor adapted for mount- -ing on a transmissionhousing comprising a cover plate adapted for mounting over an opening inthe housing, a governor mechanism mountable on the cover plate outsidethe housing, a drive shaft for the governor mechanism journalled in thecover plate, a differential gear as; sembly having one element coupledto the drive shaft and being rotatably supported by the cover plate, asleeve journalling the gear assembly and adapted to be tted in anaperture in a rst bracket in the housing, a hollow shaft having a gearthereon, journalled at one end in the sleeve adjacent the cage, thehollow shaft and one element of the differential gear being clutchedtogether, the gear being of smaller diameter than the sleeve andaperture and the sleeve of smaller diameter than the opening in thehousing, the other end of the hollow shaft being adapted for rotation inan aperture in a second bracket in the housing, a central shaftjournalled in and extending through the hollow shaft and coupled to thethird element of the differential gear, and a drive gear mounted on thecentral shaft external to the hollow shaft, the drive gear being smallenough to pass through the apertures and the opening.

12. A differential governor adapted for mounting on a transmissionhousing comprising a cover plate adapted for mounting over an opening inthe housing, a governor mechanism mountable on the cover plate outsidethe housing, a drive shaft for the governor mechanism journalled in thecover plate and having a first sun pinion thereon, a differential cagecircumjacent the pinion and rotatably supported at one end by the coverplate, a sleeve journalling the other end of the cage and adapted to betted in an aperture in a first bracket in the housing, a hollow shafthaving a gear thereon, journalled in the sleeve adjacent the cage, thehollow shaft and cage being clutched together, the gear being of smallerdiameter than the sleeve and aperture and the sleeve of smaller diameterthan the opening in the housing, the other end of the hollow shaftlbeing adapted for rotation in an aperture in a second bracket in thehousing, planet gears in the cage meshing with the first sun pinion, asecond sun pinion meshing with the planet gears and mounted on a centralshaft journalled in and extending through the hollow shaft, and a drivegear mounted on the central shaft external to the hollow shaft, thedrive gear being small enough to pass through the apertures and theopening.

13. In combination with a transmission housing, a differential governoradapted for mounting on the housing comprising a cover plate adapted formounting over an opening in the housing, a governor mechanism mountableon the cover plate outside the housing, a drive shaft for the governormechanism journalled in the cover plate and having a first sun pinionthereon, a differential cage circumjacent the pinion and rotatablysupported at one end by the cover plate, a first bracket in the housing,a sleeve journalling the other end of the cage and adapted to be fittedin an aperture in the rst bracket, a hollow shaft having a gear thereon,journalled in the sleeve adjacent the cage, said hollow shaft and cagebeing clutched together, the gear being of smaller diameter than thesleeve and aperture and the sleeve of smaller diameter than the openingin the housing, a second bracket in the housing, the other end of thehollow shaft being adapted for rotation in an aperture in the secondbracket, planet gears in the cage meshing with the first sun pinion, asecond sun pinion meshing with the planet gears and mounted on a centralshaft journalled in and extending through the hollow shaft, and a drivegear mounted on the central shaft external to the holloW shaft, thedrive gear being UNITED STATES PATENTS small enough to pass through theapertures and Number Name Date the Opening 1 503 763 Mosel y Aug. 5,1924 RENKE BRUNKEN 2,092,381 stewart Sept, 7, 1937 HARRY J- HEOIRD 52,302,714 Pollard Now/.24,1942 WAYNE R" H 2,373,453 Brunken Apr. 10,1945 REFERENCES CITED FOREIGN PATENTS The following references are ofrecord in the Number Country Date le of this patent: v 10 17,981 GreatBritain Aug. 7, 1907

